1. Field of the Invention
The present invention relates to management information maintenance in a network management system of a telecommunications network.
2. Description of the Related Art
In large telecommunications network, each deployed network resource under management is represented by a software object, or instance, in a network management system. Each instance is a logical representation of its associated deployed network resource. Since the telecommunications network comprises a plurality of deployed network resources, the network management system also comprises a plurality of associated instances.
In order to maintain consistency between the information contained in the instances (logical representations) in the network management system and that contained in the deployed network resources, each instance has the ability to synchronize its state (i.e., values of the instance's attributes) with its associated deployed network resource. For example, when a deployed network resource's state changes, the instance representing that deployed network resource is notified by the deployed resource and the instance updates its state accordingly. A network management application linked to the network management system, instead of accessing directly the deployed network resource, can access the instance representing the deployed network resource to discover the current state of the deployed network resource.
Likewise, instead of sending commands directly to the deployed network resource, the network management application can send commands to the instance of the network management system representing the deployed network resource. The instance is programmed with the ability to accept commands from the network management application and can therefore decode the original command and translate it into a format understood by the deployed network resource before sending the translated command thereto.
In the following discussion, the network management application is referred to as the Manager. The plurality of instances representing the deployed network resources under management is referred to as a Managed Information Base (MIB). Each instance within the MIB is referred to as a Managed Object (MO) instance. Specific state information maintained in each MO is referred to as Management Information (MI) of the MO. The MI of the MO may comprise configuration attributes, operational states, alarms, or any information relevant to the management of the MO. MI may also be used in certain contexts to refer to the collection of all MOs' states within the MIB. The deployed network resources are sometimes referred to as network elements (NEs). The Manager does not interact directly with the NEs, but rather interacts with the MOs either directly or indirectly, via a software component called Agent.
In a large telecommunications network, it may be common that the number of MOs exceeds hundreds of thousands in number. Although the overall network is dynamic in nature, i.e., the individual MO state changes, it is not uncommon that many kinds of MO state information are static or change very infrequently. Examples of static MO information are the operational state (e.g., most of time, the MO state is “in service” and not changed to “out-of-service”), the inventory information such as the hardware serial number or the software version and the relations with neighboring nodes.
The state-of-the-art solution does not recognize, and therefore does not take advantage of this behavior common to deployed networks.
In order to synchronize the MI of the Agent with the MI of the Manager, one prior art solution requires the Manager to obtain the whole network states (i.e. MI) regardless of the network state changes. One problem of this solution is that the Manager has to compare the obtained complete network MI with the old network MI already acquired from previous exchanges and update its old network MI accordingly. This comparison process demands a lot of resources and, thus, can create high processor load, especially when the Manager administers a large telecommunications network. Another problem of the solution is that the Agent has to send the complete network MI including unchanged MI. As it can be readily observed, sending unchanged MI wastes bandwidth between the Manager and the Agent.
Another prior art solution requires the Agent to send only MO MI that has changed during a certain time period. While this avoids sending unchanged MO MI, it also creates further problems such as, for example, sending useless and outdated MO MI changed information. For instance, if a certain NE MI has changed multiple times (e.g. from state-X to state-Y and then to state-Z) during the time period, all state information (e.g. Y and Z) would be sent, even if some of them (e.g. Y) represent useless and outdated information.
Similarly, another prior art solution, instead of using a time period, uses an index created for each modification to the MI maintained in the Agent. The Manager needs to keep track of the last requested record using the index associated thereto and also needs to place a request for each record, one at a time, up until all records are sent from the Agent. As the previously presented solution, useless and outdated MO MI changed information is also exchanged and bandwidth is wasted by multiple requests.
As can be appreciated, there is a need for an improved solution for the exchange of MI between agents and managers in telecommunications network. The present invention provides such a solution.